He poured coffee for the two of them.  Murgatroyd swung down to the floor and said, impatiently, “Chee!  Chee!  Chee!”

Calhoun absently filled Murgatroyd’s tiny cup and handed it to him.

“But this is marvellous!” he said exuberantly.  “The blue patches appeared after the plague, didn’t they?  After people recovered—­when they recovered?”

Maril stared at him.  His mind was filled with strictly professional considerations.  He was not talking to her as a person.  She was purely a source of information.

“So I’m told,” said Maril reservedly.  “Are there any more humiliating questions you want to ask?”

He gaped at her.  Then he said ruefully, “I’m stupid, Maril, but you’re touchy.  There’s nothing personal—­”

“There is to me!” she said fiercely.  “I was born among blueskins, and they’re of my blood, and they’re hated and I’d have been killed on Weald if I’d been known as ... what I am!  And there’s Korvan, who arranged for me to be sent away as a spy and advised me to do just what you said:  abandon my home world and everybody I care about!  Including him!  It’s personal to me!”

Calhoun wrinkled his forehead helplessly.

“I’m sorry,” he repeated.  “Drink your coffee!”

“I don’t want it,” she said bitterly.  “I’d like to die!”

“If you stay around where I am,” Calhoun told her, “you may get your wish.  All right, there’ll be no more questions.”

She turned and moved toward the door to the cabin.  Calhoun looked after her.

“Maril.”

“What?”

“Why were you crying?”

“You wouldn’t understand,” she said evenly.

Calhoun shrugged his shoulders almost up to his ears.  He was a professional man.  In his profession he was not incompetent.  But there is no profession in which a really competent man tries to understand women.  Calhoun, annoyed, had to let fate or chance or disaster take care of Maril’s personal problems.  He had larger matters to cope with.

But he had something to work on, now.  He hunted busily in the reference tapes.  He came up with an explicit collection of information on exactly the subject he needed.  He left the control room to go down into the storage areas of the Med Ship’s hull.  He found an ultra frigid storage box, whose contents were kept at the temperature of liquid air.

He donned thick gloves, used a special set of tongs, and extracted a tiny block of plastic in which a sealed-tight phial of glass was embedded.  It frosted instantly he took it out, and when the storage box was closed again the block was covered with a thick and opaque coating of frozen moisture.

He went back to the control room and pulled down the panel which made available a small-scale but surprisingly adequate biological laboratory.  He set the plastic block in a container which would raise it very, very gradually to a specific temperature and hold it there.  It was, obviously, a living culture from which any imaginable quantity of the same culture could be bred.  Calhoun set the apparatus with great exactitude.